Pictures of clowns are popping up all over Paris, but the joke is on you if you've ever mocked France's Internet entrepreneurs.

Underneath the face paint, funny noses and fright wigs are Internet start-up business founders who were lampooned for their early online enthusiasm. Now they're having the last laugh in an advertising campaign showcasing their success.

We are serious people, said Jean-Pierre Villaret, founder of communications consultancy June21 who came up with the idea for the campaign,

In subway stations and on street billboards, clowns complete with wigs and jaunty hats stare somberly out at passers by.

We all left our old companies to set up our own firms. Each time it was the same thing. People tell you it won't work. There's a saying in French: Your idea is just a clown's thing', Villaret told Reuters.

One of the featured clowns is Gregoire Lassalle, founder of which, typically the first port of call for people looking to book cinema tickets online.

One should demand to be taken for a clown, because it implies taking a risk in business too, Lassalle said in a video on Afterwards, people say 'Hats off, you've done something that was supposedly impossible to do'.

Anne-Laure Constanza founded online maternity products and clothes store The 34-year-old said she was ridiculed for taking on such a project and wanting a family at the same time.

The internet has allowed me to launch quite easily, she said in another clip on I probably wouldn't have had the energy to open a boutique and that's not really what excited me.

The site receives thousands of hits per day, Villaret said. It has also spawned a Facebook fan club with nearly 700 fans.

What's funny is there are a lot of people who want to be clowns, said Villaret. It shows that people want to do something different.

(Reporting by Sophie Taylor, editing by Paul Casciato)